package org.tuoren.official.util;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;

/**
 * @author zcy
 * @Description:
 * @date 2021/6/1014:37
 * @version: 1.0.0
 * 加密工具
 */
public class RsaUtil {

    private   static final String  PUNLIC_KEY="MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCdFwaDtgboAD8PMPWEGWzL6kWaCgHDCMKP2QYelK9oTxGND+0AqO5lw6SifUjOytofA/fblldV7dqrLdErH+6gOMF188Eko/XEmyT5MmMVRs4Lu71ChKiebua+5jHPbLC0sb188HtRMk1b+Mg7G5pPNLnksKPRYNG8wcBYU/1FbQIDAQAB";
    private static final String PRIVATE_KEY = "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\n";

    private static Map<Integer, String> keyMap = new HashMap<Integer, String>();  //用于封装随机产生的公钥与私钥
    public static void main(String[] args) throws Exception {
       /* //生成公钥和私钥
        genKeyPair();
        //加密字符串
        String message = "df723820";
        加密字符串：NybeW5L7OtNwARFJjmGMVyuPxLYO1vUTucEJ275NDrEzTP/MafkODsRE1r5FhON2nJOhKZXd27YAXViajDI63ToBrDRSwAnJW0DaU2kie0h8SiIrwywe8fCnNvqAdNXMSXlAKUsq8tTv4JuVbW5Emqn/gVtm0Jd5x23lOb4sBw4=
        U6fS/UlqDX346MbySxh3ZpEdZ9PL0WUykPetNpdm/Trt6uUvj5x6734pyoEj7hXtQm2hmaj7QfViHHYs2j+AqJTq9nrMYv7kxHnT0AJmVuk6gkmgkAxv6X3uIYspVR1jAfh8itySJ0i6whCXDfob6xyxE7PjGh+6KmSu70o6odE=
123456
        System.out.println("随机生成的公钥为:" + keyMap.get(0));
        System.out.println("随机生成的私钥为:" + keyMap.get(1));
        String messageEn = encrypt(message,keyMap.get(0));
        System.out.println(message + "\t加密后的字符串为:" + messageEn);
       // String messageDe = decrypt(messageEn,keyMap.get(1));
       // System.out.println("还原后的字符串为:" + messageDe);*/
        genKeyPair();
        String encrypt = encrypt("123456");
        System.out.println("加密字符串："+encrypt);
        String decrypt = decrypt(encrypt);
        System.out.printf(decrypt);
    }

    /**
     * 随机生成密钥对
     * @throws NoSuchAlgorithmException
     */
    public static void genKeyPair() throws NoSuchAlgorithmException {
        // KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象
        KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA");
        // 初始化密钥对生成器，密钥大小为96-1024位
        keyPairGen.initialize(1024,new SecureRandom());
        // 生成一个密钥对，保存在keyPair中
        KeyPair keyPair = keyPairGen.generateKeyPair();
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();   // 得到私钥
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();  // 得到公钥
        String publicKeyString = new String(Base64.encodeBase64(publicKey.getEncoded()));
        // 得到私钥字符串
        String privateKeyString = new String(Base64.encodeBase64((privateKey.getEncoded())));
        // 将公钥和私钥保存到Map
        keyMap.put(0,publicKeyString);  //0表示公钥
        keyMap.put(1,privateKeyString);  //1表示私钥
        System.out.println("公钥："+keyMap.get(0));
        System.out.println("私钥："+keyMap.get(1));
    }
    /**
     * RSA公钥加密
     *
     * @param str
     *            加密字符串
     *
     *            公钥
     * @return 密文
     * @throws Exception
     *             加密过程中的异常信息
     */
    public static String encrypt( String str) throws Exception{
        //base64编码的公钥
        byte[] decoded = Base64.decodeBase64(PUNLIC_KEY);
        RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded));
        //RSA加密
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, pubKey);
        String outStr = Base64.encodeBase64String(cipher.doFinal(str.getBytes("UTF-8")));
        return outStr;
    }

    /**
     * RSA私钥解密
     *
     * @param str
     *            加密字符串
     *
     * @return 铭文
     * @throws Exception
     *             解密过程中的异常信息
     */
    public static String decrypt(String str) throws Exception{
        //64位解码加密后的字符串
        byte[] inputByte = Base64.decodeBase64(str.getBytes("UTF-8"));
        //base64编码的私钥
        byte[] decoded = Base64.decodeBase64(PRIVATE_KEY);
        RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));
        //RSA解密
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, priKey);
        String outStr = new String(cipher.doFinal(inputByte));
        return outStr;
    }

}
